Hemodialysis patients are at risk for toxicity from various disinfecting. sterilizing, and cleaning agents used in reprocessing of hemodialyzers. The aim of the project is to develop a non-toxic, biocide capable of effective, economical sterilization and chemical cleaning of dialyzers. The potential exists or a chemical formulation which has these properties and maintains the integrity of the unit while ensuring the safety of the dialyzed blood. The chemical properties of activated chlorine dioxide (RenNew-D R) appear to fill the requirements. Additional research is required to ensure the absolute integrity of the reProcessed dialyzer and 100% safety of the patient. Significant work has been done already in addressing the basic biochemistry of the chlorine dioxide system which involves comparing it with other chemical systems which have been presented or use and found problematic: formaldehyde, glutaraldehyde, peracetic acid, and bleach. The elimination of first-use syndrome and blood component/dialyzer incompatibility are of prime importance for any chemical system under consideration. Therefore, terilant/cleaner/dialyzer unit compatibility must receive thorough investigation. Previous work and current investigations indicate that this is the essential focus of the work or Phase I. Phase II would detail the optimum formulation, use protocol and delivery system based on sound chemistry and economics.